Optional parameters:
 *
 * # database   - [none]      - The database name.
 * # host       - [localhost] - The database host.
 * # method     - [normal]    - How to read connection parameters.
 *                                     Possible values are normal, server, and
 *                                     env. The normal method reads them from
 *                                     the specified values. server reads them
 *                                     from $_SERVER where the keys to retrieve
 *                                     the values are what you specify the value
 *                                     as in the settings. env reads them from
 *                                     $_ENV and works like $_SERVER.
 * # password   - [none]      - The database password.
 * # persistent - [No]        - Indicates that the connection should be
 *                                     persistent.
 * # port       - [none]      - TCP/IP port on which PostgreSQL is
 *                                     listening.
 * # user       - [none]      - The database user.
 *
 * @package    laiketui
 * @subpackage database
 *
 * @author ketter (ketter@laiketui.com)
 * @since  3.0.0
 */
class PostgreSQLDatabase extends Database
{
    // +-----------------------------------------------------------------------+
    // | METHODS                                                               |
    // +-----------------------------------------------------------------------+
    /**
     * Connect to the database.
     *
     * @throws DatabaseException If a connection could not be created.
     *
     * @author ketter (ketter@laiketui.com)
     * @since  3.0.0
     */
    public function connect ()
    {
        // determine how to get our parameters
        $method = $this->getParameter('method', 'normal');
        // get parameters
        switch ($method)
        {
            case 'normal':
                // get parameters normally
                $database = $this->getParameter('database');
                $host     = $this->getParameter('host');
                $password = $this->getParameter('password');
                $port     = $this->getParameter('port');
                $user     = $this->getParameter('user');
                // construct connection string
                $string = (($database != null) ? (' dbname='   . $database) : '') .
                          (($host != null)     ? (' host='     . $host)     : '') .
                          (($password != null) ? (' password=' . $password) : '') .
                          (($port != null)     ? (' port='     . $port)     : '') .
                          (($user != null)     ? (' user='     . $user)     : '');
                break;
            case 'server':
                // construct a connection string from existing $_SERVER values
                $string = $this->loadParameters($_SERVER);
                break;
            case 'env':
                // construct a connection string from existing $_ENV values
                $string = $this->loadParameters($_ENV);
                break;
            default:
                // who knows what the user wants...
                $error = 'Invalid PostgreSQLDatabase parameter retrieval ' .
                         'method "%s"';
                $error = sprintf($error, $method);
                throw new DatabaseException($error);
        }
        // let's see if we need a persistent connection
        $persistent = $this->getParameter('persistent', false);
        $connect    = ($persistent) ? 'pg_pconnect' : 'pg_connect';
        $this->connection = @$connect($string);
        // make sure the connection went through
        if ($this->connection === false)
        {
            // the connection's foobar'd
            $error = 'Failed to create a PostgreSQLDatabase connection';
            throw new DatabaseException($error);
        }
        // since we're not an abstraction layer, we copy the connection
        // to the resource
        $this->resource =& $this->connection;
    }
    // -------------------------------------------------------------------------
    /**
     * Load connection parameters from an existing array.
     *
     * @return string A connection string.
     *
     * @author ketter (ketter@laiketui.com)
     * @since  3.0.0
     */
    private function loadParameters (&$array)
    {
        $database = $this->getParameter('database');
        $host     = $this->getParameter('host');
        $password = $this->getParameter('password');
        $port     = $this->getParameter('port');
        $user     = $this->getParameter('user');
        // construct connection string
        $string = (($database != null) ? (' dbname='   . $array[$database]) : '') .
                  (($host != null)     ? (' host='     . $array[$host])     : '') .
                  (($password != null) ? (' password=' . $array[$password]) : '') .
                  (($port != null)     ? (' port='     . $array[$port])     : '') .
                  (($user != null)     ? (' user='     . $array[$user])     : '');
        return $string;
    }
    // -------------------------------------------------------------------------
    /**
     * Execute the shutdown procedure.
     *
     * @return void
     *
     * @throws DatabaseException If an error occurs while shutting down
     *                                 this database.
     *
     * @author ketter (ketter@laiketui.com)
     * @since  3.0.0
     */
    public function shutdown ()
    {
        if ($this->connection != null)
        {
            @pg_close($this->connection);
        }
    }
}
?>